Aurelius steward



(No Model.)

A. STEWARD. TENSION MECHANISM FOR SEWING MACHINES.

Patented N0v.26, 1889.

will:

WITNEEEIEIE INVENTIIIR 2%zma4 fizewama'o, M W- AURELIUS STElVARD\VITEELER dy'XVILSON BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THEMANUFACTURING COMPANY, OF SAME PLACE.

TENSION MECHANISM FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent N 0. 415,951, datedNovember 26, 1889.

Application filed August 23, 1889. Serial No. 321,713.

To aZZ whom it may concern.-

Be it known that I, AURELIUS STEWARD,

of Bridgeport, county of Fairfield, State of Connecticut, have inventedan Improvement in Sewing-lllachines, of which the following description,in connection nying drawings, is a spe with the accompacification, likeletters on the drawings representing like parts. In sewing-machines,when a seam has been completed and it is desired to remove the material,it is customary to lift foot, and then with the fingers needle-thread,so that the same the presserslacken the may render freely through theeye of the needle, so as to enable the material to be removed from under the presser-foot without breaking the thread or straining theneedle.

Some sewing-machines have been provided with automatic means by which torelieve the needle thread from presser-foot is lifted.

The invention herein t tension when the 0 be described has for itsobject the production of means for releasing the stud on which turns thetension device-herein shown as a wheel held be tween washers and actedadjustment of which regulates the tension on the needle-thread. To lookand release the said stud I have provid wheel, and cooperating w upon bya spring,

ed it with a toothed ith the said wheel I have provided a slide having aprojection to engage a space or notch of the said wheel,

the said slide being loca ted, as shown, in a groove in the head of themachine, the said slide being moved to release the toothed wheel onlywhen the pre sser-foot lifter is turned to lift the presser-bar andpresserfoot, the mere rise and fall of the presserfoot, as when stitchmaterial of the machine is being run to varying thickness not effectingthe release of the said wheel and stud.

dle having fast on 1t a toothed wheel loose 011 it a spring-control andled tension device,

and a locking-slide having a projection to engage the said wheel,

combined with a presser-foot lifter and a device intermediate the saidpresser-foot lifter ing-slide to lift the latter and the said locktorelease the said (No model.)

wheel when it is desired to draw off the thread, as described.

Figure l in front elevation represents the head of a sewing-machineprovided with my improved tension mechanism; Fig. 2, a sec- 5 tion ofFig. 1 on the line 0;; Fig. 3, a detail at the inner side of thecap-plate to show the toothed wheel and part of the locking-slide, andFig. 4 a detail showing part of the presserfoot bar and the intermediateslide actuated 6 by the presser-foot lifter.

The overhanging arm A, (partially shown,) the cap-plate A, theneedle-barA the presserbar 13, the presser-foot B, its spring Bregulating-nut B arm 13, and presser-foot lifter 6 B are and may be allas usual. The capplate has a bearing in which is mounted loosely a shortspindle (1, provided between its ends with a shoulder a. At its innerend inside the cap-plate the said spindle has fixed to it a toothedwheel o the said wheel being herein represented as attached by a screw aThe spindle a, to the right of the shoulder a, receives upon it loose]ya tension wheel or device I), of usual construction, which 7 5 at oneside bears against a friction-washer (shown in black) interposed betweenthe wheel and shoulder a. The opposite side of the wheel 6 receivesagainst it, as shown, a washer 2, and next the washer on the spindle isa plate I), acted on by a spring 19 the force of which is regulated byanut 6 screwed upon the split end 12 of the spindle. The needlethread,passed once about the wh inner side of the face-plate as grooved, as at4:, to receive a locking-slide 0, (shown as a thin plate of met-ah)slotted near its upper end to embrace the inner end of the spindle, asshown in Figs. 2 and 3, the said slide having a projection 5 to enterone or the other of the notches of the wheel a when the slide ispermitted to descend to thus lock or hold the spindle. The teeth of thewheel a are pointed, as represented, to enable the projection 5 to enterreadily between the said teeth. The presser-bar is surrounded by anintermediate slide (Z, loose thereon, and having two horns 1o slot 4under the lower end In this Way the presser-bar is free to slide.

of. the lockingrise and fall according to variations in thickness ofmaterial under the presser-foot without affecting the tension but whenthe presserfoot lifter is turn ed to lift the presser-foot for theremoval of the work the said lifter first slide and the locking-slide,releases the wheel, leaving to be rotated by slight strain upon thread.

I claim- 1. The loosely-held spindl and lifts the intermediate so thatthe latter the spindle free the needlee haviu g a toothed wheel attachedto it and having a spring-controlled tension device loose thereon,combined with the locking-slide 0, having a projection to engage thesaid toothe tially as described.

2. The loosely-held spin dl d wheel, substane h aviu g a-toothed wheelattached to it and having a spring-controlled tension device loosethereon, combined with the locking-slide 0, having a projection toengage the said toothed wheel, and with the presser-foot litter andintermediate slide having horns, substantially as described.

The cap-plate having the groove 4:, the locking-slide c therein having apin 5, the shouldered spindle mounted loosely in the said cap-plate, thetoothed wheel a the spring controlled tension wheel, and thepresser-bar, combined with the presser-foot litter and the slide d,guided by the presserbar and having horns, substantially as described.

I11 testimony whereof I have signed my name to this specification. inthe presence of two subscribing witnesses.

AURELIUS STEWARD.

Witnesses:

LOUIS H. BAKER,

F. HURD.

